Gas distribution device



March 1955 A. N. CROWDER GAS DISTRIBUTION DEVICE 2 Shets-Sheet 1 Filed July 31, 1952 32, 28 GOES COO 0000 INVENTOR ALEXANDER N. CROWDER BY AM ATTORNEY March 1955 A. N. CROWDER GAS DISTRIBUTION DEVICE 2 Sheets-Sheet 2 Filed July 31, 1952 INVENTOR ALEXANDER N. CROWDER ATTORNEY United States Patent 'Ofiice 2,703,630 Patented Mar. 8,

GAS DISTRIBUTION DEVICE Alexander N. Crowder,

Research Corporation, of New York Bound Brook, N. 1., assignor to New York, N. Y., a corporation This invention relates to electrical precipitation apparatus and in particular to improved gas distribution plates and Vibrating means therefor.

It is common practice to provide perforated gas distribution plates in the gas inlet conduits or in the shell or casing of electrical precipitators adjacent the gas inlet conduits. These perforated plates aid in maintaining uniformity of gas flow through the precipitation zone.

These gas bafiles or distribution plates become coated or clogged with deposited materials which substantially lowers their eifectiveness and the efiiciency of the electrical precipitator. This is particularly true when the suspended material in the gas to be cleaned is of a cementitious nature or very moist.

It is therefore a principal objectof the present invention to provide an improved gas distribution plate and means for vibrating it.

A further object is to provide such a device which may be vibrated with a relatively small amount of power input.

Another object of the invention is to provide such a device wherein the vibrator motor may be positioned externally of the gas conduit or housing, supporting the gas distribution plates.

A further object is to provide a gas distribution plate and vibrating means therefor that is simple as to its parts, relatively inexpensive to manufacture, and adaptable over a substantially broad range of operating conditions.

These and other objects and advantages are provided by the gas distribution plate assembly of the invention which generally comprises an extended surface gas-permeable member, means suspending the gas-permeable member for limited movement about the vertical medial axis thereof, a rib member attached to the gas-permeable memher along the vertical medial axis thereof, and means for subjecting the rib member to rapping impacts.

The invention will be more particularly described with reference to the illustrative embodiments of the invention shown in the accompanying drawings in which:

Fig. l is a fragmentary vertical elevation in partial section of a horizontal flow precipitator employing the novel gas distribution plate of the invention;

Fig. 2 is a horizontal sectional view of a plurality of plates constructed in accordance with the principles of the invention;

Fig. 3 is a fragmentary plane view of one section of a typical gas distribution plate;

Fig. 4 is an enlarged detail view of one of the plate spacers shown in Fig. 2;

Fig. 5 is an enlarged vertical sectional view of the gas distribution plates of the invention;

Fig. 6 is a fragmentary front view in partial section of the assembly shown in Fig. 2 to more clearly show the plate vibrator motor and rapper bar; and

Fig. 7 is an enlarged fragmentary side view of one of the plate sections shown in Fig. 6.

With reference to the drawings and in particular to Fig. 1 thereof, 10 is the casing of a horizontal flow electrical precipitator having complementary discharge and extended surface collecting electrodes 12 and 14, respectively. The gas to be cleaned is led into the precipitator by conduit 16. Within the conduit and positioned between its upper and lower surfaces is the gas-permeable gas distribution plate assembly 18 of the invention, whereby all of the gas to be cleaned must pass through the openj ings in the plates before entering the electrostatic treating l attached along the vertical zone of the precipitator. Thus it will be seen that the distribution plates of the invention are removed from the effect of the electrical field of the precipitator.

The gas distribution plates as more clearly shown in Figs. 2, 3, and 5 of the drawings comprise a plurality of rectangular plates 20 which may be constructed of metallic sheets having punched or stamped opening 22, as illustrated, or the individual plates may be made of expanded metallic sheet as is well known in the art.

A rib member in the form of an angle iron is rigidly medial axis of one face of each plate. The rib members aid in keeping the perforated plates from bending or warping; however, their primary function is to provide a support and attachment for the vibrator bar 26 as is more fully described hereinafter. Adjacent the upper edge of each plate 20 are two holes 28 through which supporting pins 30 for the plate sections pass. The diameters of the pins are slightly less than diameters of the holes 28 so that the plates when supported by the pins are free to swing in a limited range, stiffening plates 32 having corresponding openings may be welded to plates as shown in Fig. 3.

Across the top of the gas inlet conduit there are secured two U-shaped channel brackets 34 for each plate of the assembly. The brackets are bored to snugly receive pins 30, and positioned so that the holes in the brackets are aligned with the corresponding holes 28 along the upper edge of each plate section. Across the bottom of the gas inlet are secured two U-shaped channel brackets 34' for each plate of the assembly. The brackets 34 and 34' are in vertical and horizontal alignment.

Vertically positioned between each plate in the assembly are U-sha'ped bars 38 which are attached at their upper extremities to the top surface of the gas inlet conduit. At spaced points along the U-shaped bars 38 small plate retaining members 40 are secured by bolts 42. Interposed between the members 40 and the bars 38 are spaced blocks 44 having bores adapted to receive the bolts 42. In general the spacing provided between members 40 and bar 38 is equal to the distance between the arms of U-shaped brackets 34 and 34'.

As is more clearly shown in Figs. 2, 4, and 7 of the drawings, the plates 20 are of such length and width that when they are positioned in the conduit they contact only the arms of U-shaped brackets 34 and 34 and the corresponding arms formed by bars 38 and members 40. Thus it will be seen that each plate is free to pivot and swing about the pins 30 within an area defined by the spacing between the arms of brackets 34 and 34' and the bar 38 and its plate members 40.

As hereinbefore disclosed, a vibrator bar 26 for the plates 20 is secured, for example by Welding, to the projecting edge of rib members 24 which are in turn secured to the medial line of each plate. The bar 26 extends across the entire width of the gas distribution plate assembly, and at one end passes through the end wall of the supporting structure or gas conduit, at which point there is provided a stuffing box 46 so that reciprocatory motion may be imparted to the bar by a suitable vibrator. The stulfing box also provides a gas-tight connection through the gas conduit. In the drawings a compressed air type vibrator 48 is shown positioned in operative relation to the bar 26.

In operation of the device of the invention, gas to be cleaned in the precipitator flows into the electrostatic treating zone through the perforated gas distribution plate assembly of the invention. A portion of the suspended material in the gas stream deposits on the plate sections. To remove this deposited material the vibrator motor 48 is energized and rapidly strikes the vibrator bar 26 which sets up an unusually violent shaking motion in each plate section. The violent shaking of the plate sections is obtainable with a relatively small amount of power input to the rapper motor due to the fact that the motion of the vibrator bar 26 works through a small leverage comprising the outstanding edge of each rib member-24. The vibrating bar tends to revolve each plate about the axis of the angle iron which motion, however, is limited by the U-shaped brackets 34 and 34' as hereinbefore described. Thus a fluttering motion is imparted to the entire surface of each plate, and it is cleaned of deposited material with a substantially small power input at the vibrator located on the outside of the gas flue where it is readily accessible for adjustment and repair.

From the foregoing description it will be seen that the present invention provides a novel gas distribution plate assembly whereby the aims, objects, and advantages of the invention are fully accomplished.

it will be evident that various modifications may be made in the construction of the device, and in the form of the apparatus. For example, on small gas inlet conduits a single plate section instead of the plurality of plates may be employed, and the gas distribution plates may be used equally well with vibrator motors positioned inside the gas conduit, or the plate assembly may be installed on other than horizontal flow electrical precipitators which were illustrated in the drawings by way of example only.

I claim:

1. A gas distribution device comprising a plurality of extended surface gas-permeable members, means suspending said members in co-planar spaced relation for limited movement about the vertical medial axis thereof, a rib member attached to one face of each of the gas-permeable members along the vertical medial axis thereof, a rapper bar secured to the projecting edge of each of the rib members, and motor means for vibrating said bar whereby each of said rib members are subjected to rapping impacts having a component of force spaced from and normal to the medial axis of said gas-permeable members.

2. A gas distribution device comprising a plurality of extended surface gas-permeable members, means suspending said members in co-planar spaced relation for limited movement about the vertical medial axis thereof, a rib member attached to one face of each of the gas-permeable members along the vertical medial axis thereof, guide means for each of said gas-permeable members for limiting the angular displacement of said members, a rapper bar secured to the projecting edge of each of the members, and motor means for vibrating said bar whereby each of said rib members are subjected .to rapping impacts having a component of force spaced from and normal to the medial axis of said gas-permeable members.

3. A gas distribution device comprising an extended surface gas-permeable member, means suspending said member for limited movement about the vertical medial axis thereof, a rib member attached to said gas-permeable member along the vertical medial axis thereof, and means for subjecting said rib member to rapping impacts having a component of force spaced from and normal to the medial axis of said gas-permeable member including a rapper bar secured to the projecting edge of the rib member and motor means for vibrating said bar.

References Cited in the tile of this patent UNITED STATES PATENTS 527,341 McWilliams Oct. 9, 1894 710,624 Sly Oct. 7, 1902 1,333,790 Bradley Mar. 16, 1920 1,343,482 Schmidt et al. June 15, 1920 1,356,086 Plaisted Oct. 19, 1920 FOREIGN PATENTS 450,391 Germany Oct. 7, 1927 520,598 France June 28, 1921 

